Question

According to Einstine's Theory of Relativity, time moves slower when we're closer to the ground (gravitational field). Here's the question. If one of an identical twin were to be raised on space station where time moves quicker, then after 10 years of Earth time - would they look different? Like will one of them look literally older than the other? thanks

Answer 1

Yes, difference of time will take place.

**However**, difference will be small and one of them will not look literary older than other.

In order to calculate the difference of time on Earth and in space station we can use the formula:

$$\Delta t(\text{Earth}) = \Delta t(\text{station}) \times \sqrt{1 - \frac{\varphi^2}{C^2}}$$

Where:

- $\varphi$ Gravitational potential $\varphi = -\frac{Gm}{R}$

- $G$ Gravitational constant

- $m$ Earth mass

- $R$ Earth radius

- $C$ Velocity of light

If we perform all the calculations, the difference will be a thousand fraction of a second!